EMI Big Thunder exhaust?
 

Looking into replacing my Gill/Merc system.
Anyone using EMI's in a Standard Bravo setup?
You like them?
How much power are you running through them?
Im looking at about 850HP per side...is this too much?
Are they loud?
Or you think the CMI elbow-tops are worth the extra zort.

Back4More,I can't tell you about the EMI's,but my opinion is the CMI's are the extra money.
Why you getting rid of the Gil's????

The system I have now has 3 small ports/holes about 6" from where the water jacket ends.
This does not work with my cam selection...getting too much mosture back into exhaust.

I am running about 425 thru a set. But, I don't think I would run 850 thru them. CMI's are your best bet. Or perhaps a set of Lightenings for a bit less money.

You've gone this far go for what you know will work. You don't want to $kimp on the exhaust.
Dan

Eddie Marine Thunder
 

Running 600hp through the long style bravo pipes. I had a revision problem and this cured it. I have a set of stainless EMI risers for the silent choice set up that I will let go for a good price if anybody is interested.

Sheikman

Can I ask how you knew you had a reversion problem?? What were the symptoms?

Sludge under the valve covers.

eddie Marine Thunder
 

Motor would idle fine for about 5 minutes then it would just die.

Pulled the exaust risers and looked inside the manifolds. If you see white speckled marks in the carbon or white water trails that is a water problem usually associated with revision. I had installed a larger cam also 590 intake, 610 exaust @ 112 seperation.

Sheikman

Sheikman do you have those SS risers still for sale? Greg 815-218-1603

If you put a PCV system in it that will no longer happen. I had the same problem, Sludge in my valve covers, put a PCV valve in and it was all gone.


My EMI's always have water in the bottom of the manifolds, don't know if its reversion or the cool down condensation. I am only running a 222-230 duration .543/.563 lift on a 112 LSA roller cam..


Travis

I had the same problem. White sludge under the valve covers. I noticed this after I installed EMI exhaust (short ss risers) for the existing silent choice system. It never did this with the stock mercruiser manifolds and risers. Added pcv valves to both motors and no white sludge.. crane cams 559 lift 236@ .050
114 LS.